FRIDAY, May 2, 2014 (HealthDay News) -- About one-quarter of American children aged 2 to 5 spend three or more hours a day in front of the television, computer or other media devices, which is well above limits recommended by experts, according to a new study.

Children younger than age 2 should not have any screen time, while older children should have a maximum of two hours a day, according to the American Academy of Pediatrics.

However, the latest University of Michigan Mott Children's Hospital National Poll on Children's Health shows that many children are getting too much screen time. The survey included 560 parents of children aged 1 to 5.

"In our poll, we found that one-quarter of parents of kids 2 to 5 years old are allowing more than three hours of entertainment screen time each day. That is more than is recommended," Dr. April Khadijah Inniss, a pediatrician at the University of Michigan Health System, said in a university news release.

"When you get to three or four hours each day, that screen time crowds out other important activities that babies and young kids should be engaging in: looking at books, going for walks or playing outside," Dr. Matthew Davis, director of the C.S. Mott Children's Hospital National Poll on Children's Health, said in the news release.

The AAP says parents should keep media devices out of children's bedrooms, keep family routines such as meals screen-free and have screen-free days for the entire family.

The survey found that 53 percent of parents restricted children's use of devices in their bedrooms or during family meals, while 28 percent imposed both location and time restrictions. However, 13 percent of parents did not place limits on screen time or locations.

When it came to following the AAP's recommendations, only 12 percent of parents of children younger than age 2 felt that no entertainment screen time is reasonable, while 88 percent of parents of children aged 2 to 5 felt that two hours or less of screen time per day is reasonable.

Limiting children's screen time is a challenge due to the rapidly changing nature of media, Davis noted. Placing restrictions on where devices can be used is a good first step.

"The most common approaches to limiting screen time have more to do with location than counting minutes. That makes sense. It's easier to say no smartphones at the table than to be watching the clock," Davis said.